Tire gauge



@ab 59 E923.

A.`E. HAHN. TlmE GAUGE. FILED AER. 12, 1920.

ADAM .EHA/wv f M l @a @,WMK

Patented Feb., d, i923,

sioux crrv, roi/vn.

TERE GAUGE.

Application led April 12,

To all whom t may concern:

Be it known that l, ADAM E. HAHN, a citizen of the United States, residing lat Sioux City, in the county oi Woodbury and State or iowa, have invented certain ne .f and useful linprovernents in rFire Gauges, of which the following is a specilication.

rlhis invention relates to pressure signals for automobile tires and has for its object the provision of means for preventing the damaging of a tire from which there has been a considerable loss of pressure due to slow leaks either through punctures or the tire valve and where such loss of pressure is ordinarily unknown to the driver of the ear.

Another object is to provide a pressure gauge and signalling means whereby the driver olf a car is pron'iptly notified when the pressure in a tire has, ifor any reason, dimished to such a degree that it is both unsafe and unwise to continue further travel or use of such detective tire.

- A further object ot the invention is to provide a pressure gauge which can be adjusted to any desired pressure and so constructed as to be attached to and carrier, by the valve stem of a tire, even during the pumping up of a tire; air valve pipe means being provided on the pressure gauge for filling the tire without disturbing the connections between the tire valve stern and the gauge.

With these and other' objects in view, my invention consists in the details olf construction, arrangement and combination oi parts as will be hereinafter fully described and pointed out in the accompanying drawings, in which Figure 1 is a vertical sectional view the invention.

Figure 2 is a detailed view 0i' the base plate and the signalling mechanism carried thereby.

Figure 3 is a section taken on the line 3-3 of Figure 2.

Figure 4 is a top plan view ot the spring follower.

1n the drawings, 1 indicates a valve stem of the usual construction, in the bore El or which is ordinarily located the valve mechanism by means ot which air is admitted into or discharged from the tire. Such valv mechanism forms no part or my inven -ion and has been excluded :troni the drawings as unnecessary to the description and illustration or" my invention. lt may be said 1920. Serial No. STIS-S.

that my improved pressure gauge embodies three principal sections; a pressure gauge casing 3, a locking nut. 4l and the coupler or union 5.

The member 5 comprises a cylindrical portion adapted to be iitted over the valve stem 1VV and provided with a langed portion 6. 'lhe other end ot the coupler carries an enlarged socket for the reception oi the pressure gauge casing, this socket comprising the bottom wall Y and an annular rim 8 threaded tor engagement with the lower portion of the casing A valve pipe 9 is formed integral with the tubular member extending from one side thereof immediately below the bottom socket wall 7 and extends upwardly beyond the rim 8, being provided with an internal passage 10 leading up through the wall 8 as shown at 10. A cap 1l provided with a finger grip 12 is adapted to be threaded over the outer end of the valve pipe for closing the passage. epending into the bore of the coupler 5 trom the under side of the wall 7 is a conical projection 13 provided with a central opening communicating with the olf-set passage 1li of the socket wall.

rlhe pressure gauge and sionalling mechanisin or the device is housed in the casing 3 which has one end threaded for engagement with a cap 15 and the other end threaded for engagement with the threads of the rim 8 of the coupler 5.

in exhaust nozzle 1G is welded or otherwise suitably ailired to the inner wall or the casing and is provided for threaded engagement with the lower end of the cap holder l?, an exhaust passage 16 being provided in the holder and nozzle and leading eXteriorly of the casing. A supporting plate 18 is positioned within the casing by means of the set screws 19 so as to be slightly above the nozzle 16, and in supporting engagement with the cap holder 17, as shown to advantage in Figure 3 of the drawing. rlThis plate is provided with threaded openings 20 through which are threaded adjusting screws 20. F ast-cned to the plate on opposite sides of a central opening 2l are sockets in which are received the ends ot a short axle 23 ot a trip hammer' 24. rlhe trip hammer includes a cani head portion 25 through which the axle 23 is passed and the striking arm 24e which is provided with a notch 2a for receiving the tip of a linger to facilitate movement of the hainmer to a set position. An abrupt shoulder 26 is formed: on the cam portion 25 for a purpose hereinafter' more fully explained. A spring :27 is securely fastened to the plate. 18 and is connected to the hammer being coiled about the aXle 23 so as to normally tension the hammer to swing in the direction ot' the cap holder.

A piston head 28 is disposed for vertical movement within the lcasing and carries two upright spaced rods 29, the outer ends of which are adapted to be received within the tubular shank 30 ol the adjusting screws 20. fitrip lever 3l having a broad and substantial base 32 is rigidly mounted on the pistoni 28 between the spaced rods 29 and is adapted to work through the slotted end 33' of a flexible guide member 34, ai'- iXed to the under lace 01"' the plate 18 and projecting across the path olthe trip lever. The coil spring 35 is disposed about the rods- 29 with one end secured to the piston 28 andiy the opposite end secured to a 'l'ollower 36. rlhe follower 3G is adapted for movement independent ot the piston andl is provided with circular openings 37 through which the rods 29 pass and a rectangular opening 38 'for the passage therethrough of the trip lever 8l. The lower ends ot' the adjusting screws follower and control movement ot the iollower for diminishing or increasing the er;- pansion ot the spring 85, thus permitting the spring to be tensioned in accordance with the amount of pressure desired to operate the device. Seated within the socket portion ol the coupler 5 is a flexible diaphragm preferably ot rubber and comprisingv an enlarged concaved base flange 40 providedA with a central opening 41 and an air saclt formed integral with the upper tace of the base flange, such air sackcoinw prising a rather wide upper portion 42 and a` side wall 43, the sid-e wall extending downwardly beneath the upper portion and converging inwardly' toward the center opening 4l' of the base iiange, thus providingI an expansible or collapsible diaphragm. circular metallic washer 44 is adapted to be placed on top ot thediaphragm base 40, before-'the casing 3 is screwed in place, suitablegrooves being formed in the wall 7 and washer44A to receive the enlarged rim 450i1V the diaphragm base.

The locking nut 4 has its upper lace provided with a recess, into which is inserted the base flange 6 of the coupler,` a retaining ring or washer 46, held in place by set screws 47 being seatedY upon the ilange la' to retain the nut in engagement with the coupler. rlhis washer 46 is adapted to inove freely in a circle over said lange when the nut 5 is screwed onto the valve stein l. thus permitting the nutI to be turned without revolving the casing so that' the latter is 2O bear down upon thev brought down upon the end of the valve stem in a vertical descensionI and without any lateral twist whatever. rllhe ordinary tire valve stem l has two different sets of threads on it, one set of threads 48 being on the valve stem proper and the other threads on the part 49 oi' the stein to which a dustcap is ordinarily attached. ln applying my invention onto the valve stem l to provide an air tight joint, the usual` dust cap is reY placed by a round nut 50 having itsupper i'ace provided with corrugations, concentrically disposed'. rllhis nut is screwed downuntil the top ol the valve stem portion 49 and the corrugated face of the nut are on. a horizontal plane, a circular' washer `5l being interposed between the lower tace of the nut`and the shoulder oi:` the valve stem..A il rubber washerv 52. havinga corrugated under side complementall to the corrugated lace oi" the nut is supported upon the top oi the valve stem l and isprovidedwithI al central opening through which the conical-projection 13 protrudes when the couple-r 3 is drawn down upon the valve stem.

ln setting forthy the operation of. the device, it must be assumed that the valve stein.

l has associated therewith. some one or the usual ilornis oi inlet valve mechanism by means oli which the air admitted into the tire. Assuming that such a mechanisinlisin` the bore 2 olf the valve stemhereillustratedv will be seenl that as the nut 5 is screwed about the valve stem, the coupler 5 wi'lllbe drawn downwardly uponv the stemiunt'il theV projection 13 presses against the operating:

pin ol the inlet valve mechanism sov as to open the valve and keep it open as'long as the device is attachedtot'he valve stem, thus permitting the air topass from? the tire up through the passage 14 into the air sack ot the diaphragm. rllhe diaphragm thusV eX- pands, forcing the piston 29 upwardly against the tension oit the spring 35.- and causing the trip lever 31 to bear against the cam portion of thehammer. The hara mer is then moved about its pivoty against the tension ol the spr-ing 27 until the cap shoulder 26 is engaged by the trip rod, preventing return of the harmner to its original pcsition untill removal of the' trip rod.l A

suitable concussion cap 53 havingv been` placed; in the holder 17, the device is ready lor operation. pressure within the tire below that set' for the operation ot' the device, the resistance oli the pressure within the diaphragm against the tension ot? the spring 35 will' be proportionately decreased.j permitting the piston 28 to be iorcedlby the spring against the diaphragm to such degree, at least, that the trip lever 3l willi be disengaged 'from the catch 26 ol the hain1ner,. which.

being 'free to move on itspivot will be swung.V against the concussion cap, exploding the Upon any decrease in the same and causing a sharp report suflicient to attract the drivers attention and notify him of what has occurred. The passage 16 of the exhaust nozzle and the openings 54 in the wall of the casing provides an exhaust for the concussion, permitting the report to be heard clearly. ln the preferred application of the invention, the -air inlet valve mechanism previously referred to, is removed from the valve stem l and placed in the pipe l() of the pressure gauge device so that it will not be necessary to take olf the pressure gauge in order to fill the tire, the air supply pipe being attached directly to the pipe l0, in which instance the air will be admitted through the valve mechanisin thereof into the passage l0 and through the opening l0 from which it passes under the base flange of the diaphragm into the air sack thereof and also through the passage lll into the tire valve stem l and subsequently to the inner tube of the tire.

lt will thus be seen that l have provided a pressure gauge signalling device which can be attached to the end of the ordinary tire valve stem in such a way as to have an absolutely air tight connection therewith, and at the same time permit of iilling the tire without the necessity of disturbing the connection between the valve stein and the gauge.

Having thus fully described my invention, what l claim as new and desire to secure by Letters Patent is l. casing adapted to be attached to a tire valve and adapted to communicate therewith, a diaphragm in the casing actuated by the air pressure therein, a piston in the casing engageable with the diaphragm, a spring mounted on the piston, a follower engaged with the spring member, a signal actuated by the movement of the said piston and diaphragm, means for adjusting the relationship of the follower with the piston whereby the tension of the spring is regulated and the amount of air pressure to actuate the signal can be controlled.

2. A casing adapted to be attached to a tire valve and adapted to communicate therewith, a sound emitting passage associated with the casing, a detonating cap supporting tube communicating with the said sound emitting passage, a supporting plate mounted within the casing and adapted to receive the detonating cap supporting tube, and a cap exploding device mounted on the supporting` plate and actuated by the vari.w ance of air pressure within the casing.

3. A casing adapted to be attached to a tire valve and adapted to communicate therewith, a diaphragm in the casing and actuated by the air pressure therein, a piston mounted in the casing and engageable with the diaphragm, a spring mounted on the piston, a follower engaged with the spring member, pins rising from the piston and extending through the follower, a supporting plate mounted within the casing, a signal actuated by the movement of the said piston and diaphragm, set screws threaded through the said supporting plate and having their shanks tubular to receive the upper ends the pins carried by the piston for adjusting the relationship of the follower with the piston whereby the tension of the spring regulated and the amount of yair pressure to actuate the signal can be controlled.

ln testimony whereof affix my signature in presence of two witnesses.

ADAM E. llftlrlll. lWitnesses ALFRED l?. AHN, ELLA hrrsnmmN. 

